Lightning Seed. The Alien Reveal

In an icebound future devastated by climate change, an army of religious extremists steal an ancient alien weapon and head for the remains of Las Vegas. Their plan – fix the weather and save the world. It’s a plan that could finally destroy Earth’s fragile climate and the wprld’s few remaining survivors.
All that stands between them are two people; an amnesiac teenager with uncanny abilities who can access the device, and a war-weary, embittered veteran who’s seen her fair share of conflict.